Electrical automatic shift control system with hilly country detecting unit

ABSTRACT

The present invention relates to an electrical automatic shift control system with a hilly country detecting unit which is adapted for use with an automatic transmission for automobiles comprising a fluid type torque converter transmission with a speed change gear, friction engaging means for accomplishing shifting gear engagements of the speed change gear, and a hydraulic actuation circuit for controlling the friction engaging means. The automatic shift control system comprises a climbing road condition logic circuit, a downhill road condition logic circuit and a memory circuit, whereby it functions such that the control unit of the torque converter for effecting normal automatic gear changes in a hilly country is properly restrained from changing to top gear thereby automatically and easily preventing the transmission from changing to top gear on inclines and declines and on curved roads, while this hilly country driving condition is released upon changing into level road running.

United States Patent 11 1 1111 Sakakibara et al. 1 Jan. 30, 1973 s41ELECTRICAL AUTOMATIC SHIFT 3,448,640 H1969 Nelson ..74/866 CONTROLSYSTEM w 'r BILLY 3,572,168 3/1911 Shirai et al ..74/7s2 A COUNTRYDETECTING UNIT Primary ExaminerArthur G. McKeon [75] Inventors: ShigeruSakakibara, Aichi-ken; Attorney cushman, Darby & Cuvshman Takaaki Kato,Toyohashi-shi; Katsunori Ito, Kariya-shi, all of Japan 57 ABSTRACT 1Assignees: Jidosha 983 Kabu$hiki The present invention relates to anelectrical autoyf i PPf matic shift control system with a hilly countrydetect- Kabushlki Kalsha! y i Japan ing unit which is adapted for usewith an automatic [22] Filed. Sept 17,1970 transmission for automobilescomprising a fluid type torque converter transmission with a speedchange PP O- 73,158 gear, friction engaging means for accomplishingshifting gear engagements of the speed change gear, and a ForeignApplication Priority Data hydraulic actuation circuit for controllingthe friction engaging means. The automatic shift control system Sept.27, 1969 Japan ..44/77247 mprisgs a climbing road conditionlogiocircuit, a Oct-20.1969 Japan downhill road condition logic circuitand a memory P circuit, whereby it functions such that the controlunitFeb. l2, i970 Japan ..45/|238l of the torque onverter for effectingnormal automatic gear changes in a hilly country is properly restrainedCl ..74/645, 7 from changing to top gear thereby automatically and74/731 easily preventing the transmission from changing to Cl -F16|lF16h 360k 21/00 top gear on inclines and declines and on curved roads,[58] Field Of Search ..74/73l, 752 [L866 while this hilly countrydriving condition is released upon changing into level road running.[56] References Cited 12 Claims, 39 Drawing Flgures UNITED STATESPATENTS 3,267,762 8/1966 Reval ..74/866 X x 8 20 3a /0\ F 1 i 1 2 63 b 5g 40\ 43 x X \\I *X I .x z 9/ V I XI,

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SHEET D10!7 23 REAR BRAKE 42 44 4 SECOND DISTRIBUTOR VALVE FIRST lusmauron VALVE SHIFT REGION PAIENIEII JAN 30 I975 SHEET OEIIF 23 FRONTBRAKE\ F 2 cLft'jfifig l) FRONT CLUTCH l SHEET DBUF 23 PATENTED JAN 30I975 //v CAR SPEED) 0 124; //v 64!? SPEED ECU/WENT) Tmous cavvmrmTIRE/NE SHAFT RE'VULUWOV N2 sum 05 0F 23 PATENTED JAN 30 I973 PMENTEDJAN 30 I975 SHEET 10UF 23 LOGICZLCKT DOMVH/LL LOG/O41. CKT lPAIENIEnJmmma 3713.351

3 sum 12m 23 PATENTEUJAN 30 I975 SHEET 17UF 23 NM wt PATENTED JAN 30I975 SHEET 18UF 23 PATENTEDJM30 197s SHEET lSUF 23

1. An improved electrical automatic shift control system for an enginedriven vehicle for controlling an automatic transmission systemcomprising: a torque converter including an input shaft, a pumpconnected thereto, and a torque converter output turbine driven thereby,a speed change gear unit connected to said turbine, friction engagingmeans for selectively accomplishing the gear changing engagements ofsaid speed change gear unit, and a hydraulic actuation circuit forcontrolling said friction engaging means including; a shift regionsetting valve and at least one distributor valve for distributing anactuating oil to said friction engaging means, and an electrical controlmeans for controlling the operation of said distributor valve of saidhydraulic actuation circuit wherein the improved electrical controlmeans comprises: a hilly country detecting unit including: a climbingroad condition responsive logic circuit, a downhill road conditionresponsive logic circuit, a hilly country releasing condition responsivelogic circuit, each of said means selectively activated to produceoutput signals indicative of their respective conditions; and a memoRycircuit, producing an output control signal for the control means,having at least two stable states and respondingly coupled to each ofsaid three circuits so as to assume one stable state thereof andproducing the output control signal upon application thereto of therespective signal from at least one of the following: the climbing roadcondition logic responsive circuit and the said downhill road conditionresponsive logic circuit and assuming the other stable state thereof andproducing no output control signal upon application thereto of thesignal from said hilly country releasing condition responsive logiccircuit, thereby operating said distributor valve in accordance withsaid output control signal of said hilly country detecting unit.
 1. Animproved electrical automatic shift control system for an engine drivenvehicle for controlling an automatic transmission system comprising: atorque converter including an input shaft, a pump connected thereto, anda torque converter output turbine driven thereby, a speed change gearunit connected to said turbine, friction engaging means for selectivelyaccomplishing the gear changing engagements of said speed change gearunit, and a hydraulic actuation circuit for controlling said frictionengaging means including; a shift region setting valve and at least onedistributor valve for distributing an actuating oil to said frictionengaging means, and an electrical control means for controlling theoperation of said distributor valve of said hydraulic actuation circuitwherein the improved electrical control means comprises: a hilly countrydetecting unit including: a climbing road condition responsive logiccircuit, a downhill road condition responsive logic circuit, a hillycountry releasing condition responsive logic circuit, each of said meansselectively activated to produce output signals indicative of theirrespective conditions; and a memoRy circuit, producing an output controlsignal for the control means, having at least two stable states andrespondingly coupled to each of said three circuits so as to assume onestable state thereof and producing the output control signal uponapplication thereto of the respective signal from at least one of thefollowing: the climbing road condition logic responsive circuit and thesaid downhill road condition responsive logic circuit and assuming theother stable state thereof and producing no output control signal uponapplication thereto of the signal from said hilly country releasingcondition responsive logic circuit, thereby operating said distributorvalve in accordance with said output control signal of said hillycountry detecting unit.
 2. The improved electrical automatic shiftcontrol system according to claim 1, wherein said downhill roadcondition responsive logic control circuit comprises: means responsiveto the running state of the vehicle including: vehicle accelerationsignal generator means for producing a signal indicative of a selectedacceleration rate, a gear position circuit responsive for producingsignals indicative of each gear position,
 3. The improved electricalautomatic shift control system according to claim 1 wherein said hillycountry releasing condition responsive logic circuit comprises: arevolution setting operational circuit means responsive for producingsignals indicative of input and output revolution rates of said torqueconverter and transmission, a slip operating circuit responsive toselected outputs of the revolution setting means for producing slip rateratio outputs indicative of differentials in torque converter input tooutput rates, a gear position responsive circuit for producing outputsignals indicative of respective gear position engagements, meansresponsive to said revolution setting operational circuit for producingsignals respectively indicative of vehicle speed and acceleration, firstAND circuit means for generating a conditioning output signal inresponse to the respective outputs representing a selected; slip rateratio, gear position; and speed and acceleration rates; second ANDcircuit means having a first input responsively coupled to said firstAND circuit and; a synchronous timer circuit responsively coupled tosaid first AND circuit output for inhibiting its output signal unlesssaid first AND circuit output is present for at least a minimum selectedduration thereby checking the integrity of said hilly country releaseoutput.
 4. The improved electrical automatic shift control systemaccording to claim 1 wherein slip operating circuit means, coupled tosaid torque converter produces outputs indicative of selected speedratios of said torque converter and said climbing road conditionresponse logic circuit produces a required output signal in accordancewith a selected output of said slip operating circuit means below apredetermined value.
 5. The improved electrical automatic shift controlsystem according to claim 1 wherein said climbing road conditionresponsive logic circuit produces an appropriate output signal inaccordance with; a high speed gear engagement position of thetransmission; a speed ratio of a selected range, produced in response toinput and output rates of the torque converter; a change in gearengagements to a next lower range; and substantial change in the speedratio signal indicative of a nonengine braking condition; while vehicleacceleration responsive means produces an output below a selectedmaximum to indicate limited acceleration.
 6. The improved electricalautomatic shift control system according to claim 1 wherein saidclimbing road condition responsive logic circuit comprises: first ANDcircuit means for generating an output signal upon application theretoof a signal representing that the transmission is in a second gearposition, a signal representing the vehicle speed is higher than asElected value, and a signal representing a speed ratio between thespeeds of the input and output of said speed change gear, and the torqueconverter input is below a selected value; second AND circuit means forgenerating an output signal when the signal of said first AND circuit isapplied to said second AND circuit directly; and a synchronous timercircuit for checking the duration of said first AND circuit means signalto produce an enabling input for said second AND circuit if said firstsignal is of a selected minimum duration.
 7. The improved electricalautomatic shift control system according to claim 1 wherein saiddownhill road condition responsive logic circuit comprises: a brakingpressure signal generator responsive to a vehicle braking actuator, asynchronous timer circuit actuated in response to the signal from saidbraking pressure signal generator of a selected minimum duration, andAND circuit means for generating an output signal upon applicationthereto of the signals from said brake pressure signal generator andsynchronous timer circuit.
 8. The improved electrical automatic shiftcontrol system according to claim 1 wherein said downhill road conditionresponsive logic circuit comprises: circuit means responsive to provideindication of a minimum vehicle tilt angle, a synchronous timer circuitresponsive thereto for timing the duration of said vehicle tilt, abraking lamp lighting signal generator circuit responsive to a vehiclebraking actuator, a top gear position responsive circuit, and ANDcircuit means for generating an output signal upon application theretoof the signal from said four circuits.
 9. The improved electricalautomatic shift control system according to claim 1 wherein said hillycountry releasing condition logic circuit comprises: a first gearposition responsive circuit generating a signal relative thereto, arevolution setting operational circuit for generating an output signalwhen the speed of the output of the transmission becomes lower than aselected value representing that the vehicle is about to come to astandstill, and AND circuit means for generating an output signal uponapplication thereto of the signals from said two circuits.
 10. Theimproved electrical automatic shift control system according to claim 1wherein said hilly country releasing condition responsive logic circuitcomprises: a revolution setting operational circuit for producing anoutput signal when the number of revolutions of the output of thetransmission exceeds a selected value representing that the vehicle isrunning at a high speed.
 11. The improved electrical automatic shiftcontrol system according to claim 1 wherein said hilly country releasingcondition responsive logic circuit comprises: first AND circuit meansfor generating an output signal upon simultaneous application thereto ofa signal representing a speed ratio between the speeds of the input andoutput of said torque converter which is higher than a selected lowerlimit and a signal representing said speed ratio which is below aselected upper limit, said two signals being indicative of said speedratio which is within a selected range of values near 1.0, a signalrepresenting that the transmission is in a second gear position, and asignal representing the vehicle maintains a speed higher than a selectedspeed; and second AND circuit means for generating an output signal uponapplication thereto of the signal directly introduced from said firstAND circuit and a signal introduced through a synchronous timer circuitresponsive for inhibiting said second AND signal unless said first ANDsignal is of a selected minimum duration.